The present invention relates to a sheet feed control device and a sheet feed control method in a printer.
A continuous form print sheet is used in printing data fed from a personal computer or the like, in which a perforated score line is formed in the widthwise direction of the sheet so that a printed page can be separated at the line of the perforations. When printing, the sheet is advanced by a feeding means to a position where printing is effected. Upon completion of one page of printing, a change-of-page signal is issued. In response thereto, the sheet is advanced to a position where an initial printing position of the next page confronts a printing station. In order to tear-off the printed page, the feeding means is driven to further advance the sheet by a predetermined distance by manipulation of a switch so that the perforated score line at the bottom of the printed page is brought to be in coincidence with a cutting means located downstream of the printing station.
However, such a sheet feeding is applicable only in the cases where a first line distance or an upper margin of the print sheet reserved between the leading edge of the sheet and the initial printing line is prefixed whatsoever the kind of the sheet may be, or the upper margin is determined by a total distance of a prefixed distance and a variable distance specified by a change-of-line signal posed ahead of the first line print position. Of the print sheets on which a format, such as border lines or ruled lines indicative of printing positions, etc., has previously been printed, the initial printing position is required to be accurately positioned in the printing position. In order to know if this positioning is precisely accomplished, a test printing is performed and, if unsatisfactory, an appropriate number of interline spacing instruction is inserted ahead of the printing data to further adjust the sheet position relative to the printing station. The perforated score line of the sheet can thus be brought to be in coincidence with the cutting means. However, the loading of the print sheet in such a way has proven to be intricate.
It is conceivable to load the continuous form print sheet in the printer in such a manner that upon coinciding the initial printing position with an index provided in the printer, the feeding means is driven to advance the sheet by a predetermined distance to thereby coincide the initial printing position with the printing position. While such a method is advantageous in that loading of the sheet is facilitated, a difficulty exists in that the perforated score line cannot coincide with the cutting means, since a distance between the leading edge of the incoming page and the initial printing line is not memorized in the printer.